US Patent 10896931 3D semiconductor device and structure

A 3D semiconductor device, the device including: a first level including a first single crystal layer and first transistors, where the first transistors each include a single crystal channel; first metal layers interconnecting at least the first transistors; and a second level including a second single crystal layer and second transistors, where the second level overlays the first level, where the second transistors are horizontally oriented and each include at least two side gates, where the second level is bonded to the first level, and where the bonded includes oxide to oxide bonds.